With intelligent development of communication devices, smart terminal devices are used more and more frequently in daily life. Various activities such as video communication, calling, voice communication, music listening, video playback, and the like can be carried out by the smart terminal device. Sounds output by the terminal device can be received by an earphone worn on a user. When the user listens to music or answers a call via the earphone, some control operations such as playing, pausing, adjusting volume, switching songs, and opening a contact list may be involved. Generally, these control operations can be realized by performing operations on a related page of a corresponding application in the terminal device, or on preset control buttons of the earphone.
However, in some application scenarios, for example, the user is in a motion state, the terminal device is placed in the user's pocket, and the terminal device is in a screen-off state, it is inconvenient for the user to perform operations on the terminal device. When performing operations on the preset control buttons of the earphone, the user needs to find a wired control button or a touch button disposed at a certain position of the earphone, and then performs a corresponding operation, which is prone to trigger a wrong control operation, thereby reducing operation efficiency. In addition, more and more users use earphones without control buttons, such that controls on applications of the terminal device cannot be realized quickly and conveniently through the user operations, thereby bringing inconvenience to the users.